Process of preparing motor fuels



May 13, 1930. F. A. HOWARD PROCESS OF PREPARING MOTOR FUELS Filed-July21, 1922 I gnvemtoz Fran/(OT/You ara Patented May 13, 1930 UNITED STATESPATENT- OFFICE FRANK A. HOWARD, OF ELIZABETH, NEW JERSEY, ASSIGNOR TOSTANDARD OIL DEVELOPMENT COMPANY, A CORPORATION OF DELAWARE PROCESS OEPREPARING MOT OR FUELS Application filed July 21, 1922. Serial No.576,578.

price is necessarily characterized by the presence of heavier fractionsand constituents which modify certain features of engine efficiency; inparticular a common result being detonation or knocking on compressionsabove a relatively medium ratio; "Various proposals have been made tomodify such detonative combustion by addition of chemical agents, butthese where effective not only add to the expense but introduce othercomplications. By my invention however, I pro-- duce an improved motorgasoline while avoiding the addition of such foreign substances.

Instead, the hydrocarbons themselves are so altered, by suitablemeasures, as to reduce the knocking propensities referred to.

In proceeding according to my invention, I segregate the heavierfractions of gasoline and conduct them in vapor state together with airor oxygen through a heated passage giving a working temperature of 450to (300 F., at a pressure not materially exceeding atmospheric. Theamount of air is controlled in such limits as to avoid materialoxidation on the hydrocarbon molecules, and will not exceed four atomsofoxygen figured to the average molecular weight of the hydrocarbon. Ingeneral I prefer an air feed within the limits of 5 to 20 cubic feet perpound of hydrocarbon. The products-are then recovered in a condenser,treated to remove gumming constituents, for example by being washed inwater or subjected to steam or preferably steam-distillation, and beingtreated with a dilute alkali solution, such as to 2% sodium hydroxidsolution, and after Washing with water are mixedcback with the lighterfractions of the gasoline from which they were primarily separated.

As an illustrative example, taking a commercial gasoline having aninitial boiling point of 110 F., 20%otf at 202 F., 50)? off at 275 F.,and 90% ott' at. 370 F., and an acid absorption of 8%, I separated offthe light fractions boiling up to 260 F., by distillation, and settingthis distillate aside I passed the heavy fractions in vapor formtogether with air through a heated passage at substantially atmosphericpressure and an effective temperature of 550 F., the air proportionbeing on the order of 11.5 cu. ft. of air per pound of hydrocarbon. Theproducts proceeded through a water-cooled condenser, and the condensateobtained was subsequently distilled with superheated steam, then treatedwith a 1%-"sodium-hydroxidsolution and washed with water, and wasfinally mixed back with the light fractions separated out from theoriginal gasoline. The product showed an initial boiling point of 1161*., 20% oil at 198 F., 50% off at 257 F. and

lVherc blended gasolines are being made, the heavy component thereformay be subjected to the oxygen and heat treatment, etc. and then bemixed with the lighter components to make up the finished gasoline.

In the accompanying drawing a suitable apparatus is shown for carryingout my process, although other forms may be equally satisfactory. Thereference character 1 refers to a still of the type commonly called arerun still. The feed oil containing boththe light fractions, which arenot to be subjected to the oxygen heat treatment, and the heavier, knockproducing fractions, which are to be subjected to the above notedtreatment, is admitted by line 2. The vapors leave the still by line 3to the rectifying column 4, in which the separation between the heavierand lightor fractions occurs, the latter being condensed in thecondenser 5 while the former, now in the liquid state, is forced by pump6 to the heating coil 7. The heavy fractions are vaporized in coil 7 andflow to the heated zone 8 into which air is admitted by line 9. The

90% off at 36Q9fF .and an acid absorption of steam still 12 Which isfitted with a tower 13 and steam spray 14, as is customary. The bulk ofthe oil is distilled by the aid of steam and is condensed and cooled ina condenser 15 from which it is discharged to a small work tank 16. Apump 17 then forces the distillate through mixers 18 and 19 into whichsoda solution and water are fed for treating and washing the oil, as iswell understood. Continuous mixers are shown but other types may beemployed. Each mixer is supplied with a separator 18 and 19respectively, which permits the separation of the mixture dischargedfrom the mixers into aqueous and oily layers. The aqueous layers aredrawn off by pipes for that purpose. I

The oily layer flowsfrom separator 18 to mixer 19 and from-separator 19to a blending tank 20. The lighter untreated fractions of the gasoline,which are removed by distillation from tower 4 and are condensed in thecondenser 5, are also conducted to blending tank 20 and the resultingmixture comprising a superior motor fuel may be withdrawn to storage(not shown).

Products prepared according" to the present invention show a superiorperformance in en ine usage.

I he expression knocking constituents, where occuring in the claimshereinaftegis which occasion detonation or knocking in carburetor-fedengines where running on compressions exceeding a relatively mediumratio.

While in describing my invention I have referred to certain specificexamples of procedure, uses,*etc. it will be understood that these areillustrative and not limitativc, and

the invention is to be regarded as limited only as defined in thefollowing claims, in which it is my intention to claim all inherentnovelty as broadly as the prior art permits. WVhat I claim is:

1. The process of preparing motor fuel, which comprises separating thelight fractions of gasoline from the heavy fractions and reserving thelight fractions, vaporizing the heavy fractions and passing the vapor atsubstantially atmospheric pressure, together with air through atemperature zone of450 to 600 F., the proportion of air being about 11to 12 cubic feet per pound of hydrocarbon, collectingcond8IlSlbl8'Pl'0dl1CtS, distilling said products with superheatedsteam, treating with'dilute alkali solution, washing with water, andmixing the washed product with the reserved light fractions originallyseparated from the gasoline.

2. The process of preparing motor fuel, which comprises vaporizing heavyhydroto be understood as referringto'constituents f carbon fractionsintended for a blended gasoline, passing the vapor at substantiallyatmospheric pressure, together with air through a temperature zone of450 to 600 F., the proportion of air being about 11 to 12 cubic feet perpound of hydrocarbon, collecting condensible products, distilling saidproducts with superheated steam,'treating with dilute alkali solution,washing with water, and mixing the washed product with light fractionsto make up a gasoline.

3. The process of preparing motor fuel, which comprises separating thelight fractions of gasoline from the heavy fractions and reserving thelight fractions, vaporizing the heavy fractions and passing the vapor atsubstantially asmospheric pressure, together.

with air through a temperature zone of 450 to 600 F., the proportion ofair being between 5 and 20 cubic feet per pound of hydrocarbon,

collecting condensible products, distilling said products with steam,treating with dilute alkali solution, washing with water, and mixing thewashed product with the reserved light fractions originally separatedfrom the gasoline.

4. The process of preparing motor fuel, which comprises vaporizing heavyhydrocarbon fractions intended for a blendedgasoline, passing the vaporat substantially atmospheric pressure together with. air through atemperature zone of 450 to 600 F., the

proportion of air being between 5 and 20 cubic eet per pound ofhydrocarbon, collecting condensible products, distilling said productswith steam, treating with dilute alkali solution, washing with water,and mixing the washed product with light fractions to make up agasoline.

5. The process-of preparing mot'or fuel, which comprises separating thelight fractions of gasoline from the heavy fractions and reserving thelight fractions, vaporizing 'the heavy fractions and passing the vaporat substantially atmospheric pressure, together with oxygen through atemperature zone of 450 deg. to 600 deg. F., treating the products toremove gumming constituents, and mixing the product with reserved lightfractions originally separated from the gasoline.

6. The process of preparing a motor fuel, which comprises separating thelight fractions of gasoline from the heavy fractions and reserving thelight fractions, vaporizing the heavy fractions and passing the vapor atsubstantially atmospheric pressure, together with oxygen, through atemperature zone of 450 to 600 F., and mixing theproduct with thereserved light fractions originally separated from the gasoline.

7. The process according toclaim 6 in which the fraction treatedwith'oxygen boils substantially entirely above 260 F.

FRANK A. HOWARD.

